What side effect can SSRIs cause in the elderly?

The side effect that SSRIs (selective serotonin reuptake inhibitors) can cause in the elderly is hyponatremia, which refers to a low sodium concentration in the blood. This condition is particularly relevant in older adults due to various factors such as age-related changes in renal function, the presence of multiple comorbidities, and the potential for polypharmacy, where various medications are prescribed concurrently.

In elderly patients, the use of SSRIs can lead to the syndrome of inappropriate antidiuretic hormone secretion (SIADH), which results in excess water retention and dilution of sodium levels in the body. This can manifest as confusion, seizures, or altered mental status, which can be particularly concerning in this population.

While other side effects such as hypertension, insomnia, and weight gain can occur with SSRIs, they are not as directly associated with the specific physiological vulnerabilities seen in the elderly as hyponatremia is. The heightened risk of hyponatremia underscores the need for careful monitoring of electrolyte levels when initiating treatment with SSRIs in older patients.